fix for BIESt #957

Merge request studip/studip!554

19 files changed, 57 insertions, 32 deletions

diff --git a/lib/classes/Assets.class.php b/lib/classes/Assets.class.php
index 1d9c23f..dd82073 100644
--- a/lib/classes/Assets.class.php
+++ b/lib/classes/Assets.class.php
@@ -145,7 +145,7 @@ class Assets
 
         $parts = explode('/', $source);
 
-        $size = $opt['size'];
+        $size = $opt['size'] ?? null;
 
         $opt = Assets::parse_attributes($opt);
 
diff --git a/lib/classes/Avatar.class.php b/lib/classes/Avatar.class.php
index b355a8a..dab3f75 100644
--- a/lib/classes/Avatar.class.php
+++ b/lib/classes/Avatar.class.php
@@ -244,7 +244,7 @@ class Avatar {
             $opt['class'] = $this->getCssClass($size);
         }
 
-        if (is_string($opt['title']) && $opt['title'] !== html_entity_decode($opt['title'])) {
+        if (isset($opt['title']) && $opt['title'] !== html_entity_decode($opt['title'])) {
             // Decode already htmlready encoded titles (which were used until
             // all attributes were encoded inside this method)
             $opt['title'] = html_entity_decode($opt['title']);
diff --git a/lib/classes/Log.php b/lib/classes/Log.php
index 22c9f6c..335572d 100644
--- a/lib/classes/Log.php
+++ b/lib/classes/Log.php
@@ -119,9 +119,7 @@ class Log
     public static function set($name = '', $log_handler = null)
     {
         $name = mb_strlen($name) ? $name : 0;
-        if (isset(self::$instances[$name])) {
-            $old = self::$instances[$name];
-        }
+        $old = self::$instances[$name] ?? null;
         self::$instances[$name] = new Log($log_handler);
         return $old;
     }
@@ -255,4 +253,4 @@ class Log
         }
         throw new BadMethodCallException('Unknown method called: ' . $name);
     }
-}
\ No newline at end of file
+}
diff --git a/lib/classes/NotificationCenter.class.php b/lib/classes/NotificationCenter.class.php
index dce878e..aaaa9e8 100644
--- a/lib/classes/NotificationCenter.class.php
+++ b/lib/classes/NotificationCenter.class.php
@@ -57,6 +57,8 @@ class NotificationCenter
             $event = '';
         }
 
+        $predicate = null;
+
         if ($object) {
             $predicate = is_callable($object)
                 ? $object
@@ -65,9 +67,10 @@ class NotificationCenter
                   };
         }
 
-        self::$observers[$event][] =
-            ['predicate' => $predicate ?: NULL,
-                  'observer'  => [$observer, $method]];
+        self::$observers[$event][] = [
+            'predicate' => $predicate,
+            'observer'  => [$observer, $method]
+        ];
     }
 
     /**
diff --git a/lib/classes/PageLayout.php b/lib/classes/PageLayout.php
index e40b22b..a8f3ffa 100644
--- a/lib/classes/PageLayout.php
+++ b/lib/classes/PageLayout.php
@@ -463,7 +463,7 @@ class PageLayout
      */
     public static function isHeaderEnabled()
     {
-        return self::$display_header && !$GLOBALS['_NOHEADER'];
+        return self::$display_header && empty($GLOBALS['_NOHEADER']);
     }
 
     /**
diff --git a/lib/classes/RangeConfig.class.php b/lib/classes/RangeConfig.class.php
index c384661..fc90434 100644
--- a/lib/classes/RangeConfig.class.php
+++ b/lib/classes/RangeConfig.class.php
@@ -52,7 +52,7 @@ class RangeConfig extends Config
             $range_id = $range_id->getRangeId();
         }
 
-        if (static::$instances[$range_id] === null) {
+        if (!isset(static::$instances[$range_id])) {
             static::$instances[$range_id] = new static($range_id);
         }
         return static::$instances[$range_id];
@@ -121,7 +121,7 @@ class RangeConfig extends Config
             }
             while ($row = $statement->fetch(PDO::FETCH_ASSOC)) {
                 $this->data[$row['field']] = $this->convertFromDatabase(
-                    $this->metadata[$row['field']]['type'],
+                    $this->metadata[$row['field']]['type'] ?? 'string',
                     $row['value'],
                     $row['field']
                 );
diff --git a/lib/classes/Request.class.php b/lib/classes/Request.class.php
index 410a74f..71c593e 100644
--- a/lib/classes/Request.class.php
+++ b/lib/classes/Request.class.php
@@ -114,7 +114,7 @@ class Request implements ArrayAccess, IteratorAggregate
     {
         $host = $_SERVER['SERVER_NAME'];
         $port = $_SERVER['SERVER_PORT'];
-        $ssl  = $_SERVER['HTTPS'] == 'on';
+        $ssl  = isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] === 'on';
 
         if ($ssl && $port != 443 || !$ssl && $port != 80) {
             $host .= ':' . $port;
diff --git a/lib/classes/SemBrowse.class.php b/lib/classes/SemBrowse.class.php
index 1bc822b..82b683f 100644
--- a/lib/classes/SemBrowse.class.php
+++ b/lib/classes/SemBrowse.class.php
@@ -1168,7 +1168,7 @@ class SemBrowse {
         if (!$option['visible'] || $option['target'] != $target) {
             return null;
         }
-        if (!$option['url']) {
+        if (empty($option['url'])) {
             switch ($option_name) {
                 case 'courses':
                 case 'semtree':
diff --git a/lib/classes/SkipLinks.php b/lib/classes/SkipLinks.php
index c5738b2..e2744b9 100644
--- a/lib/classes/SkipLinks.php
+++ b/lib/classes/SkipLinks.php
@@ -101,4 +101,20 @@ class SkipLinks
         }
         return $GLOBALS['template_factory']->render('skiplinks', compact('navigation'));
     }
+
+    /**
+     * Checks if there is another link at the same position and if it is overwritable.
+     *
+     * @return boolean true if the link at the same position is overwritable
+     */
+    private static function checkOverwrite($link)
+    {
+        if (isset(self::$position[$link['position']])) {
+            return false;
+        }
+        if (empty($link['overwrite'])) {
+            self::$position[$link['position']] = true;
+        }
+        return true;
+    }
 }
diff --git a/lib/classes/Smiley.php b/lib/classes/Smiley.php
index 803a5f4..8d37e4f 100644
--- a/lib/classes/Smiley.php
+++ b/lib/classes/Smiley.php
@@ -224,7 +224,7 @@ class Smiley
      */
     public static function getShort()
     {
-        if (class_exists('DBManager') && !$GLOBALS['SMILEY_NO_DB']) {
+        if (class_exists('DBManager') && empty($GLOBALS['SMILEY_NO_DB'])) {
             if (self::$shortnames === null) {
                 $query = "SELECT short_name, smiley_name FROM smiley WHERE short_name != ''";
                 self::$shortnames = DBManager::get()->query($query)->fetchGrouped(PDO::FETCH_COLUMN);
diff --git a/lib/classes/StudipPDO.class.php b/lib/classes/StudipPDO.class.php
index c73bb7e..8e67c34 100644
--- a/lib/classes/StudipPDO.class.php
+++ b/lib/classes/StudipPDO.class.php
@@ -43,7 +43,7 @@ class StudipPDO extends PDO
         // method that is executed on every call to the database)
         $this->query_count += 1;
 
-        if ($GLOBALS['DEBUG_ALL_DB_QUERIES']) {
+        if (!empty($GLOBALS['DEBUG_ALL_DB_QUERIES'])) {
             $trace = debug_backtrace();
 
             $classes = [];
diff --git a/lib/classes/StudipPDOStatement.php b/lib/classes/StudipPDOStatement.php
index 51972ed..5aab1cc 100644
--- a/lib/classes/StudipPDOStatement.php
+++ b/lib/classes/StudipPDOStatement.php
@@ -118,6 +118,8 @@ class StudipPDOStatement implements IteratorAggregate
         }
 
         // emulate prepared statement if necessary
+        $emulate_prepare = false;
+
         foreach ($this->params as $key => $param) {
             if ($param['type'] === StudipPDO::PARAM_ARRAY ||
                 $param['type'] === StudipPDO::PARAM_COLUMN ||
diff --git a/lib/classes/URLHelper.php b/lib/classes/URLHelper.php
index a36cc10..ae83022 100644
--- a/lib/classes/URLHelper.php
+++ b/lib/classes/URLHelper.php
@@ -169,8 +169,14 @@ class URLHelper
     {
         $link_params = $ignore_registered_params ? [] : self::$params;
 
-        list($url, $fragment) = explode('#', $url);
-        list($url, $query)    = explode('?', $url);
+        // Separate the query and the fragment parts (if any) from the main part of the URL
+        if (strpos($url, '#') !== false) {
+            list($url, $fragment) = explode('#', $url);
+        }
+
+        if (strpos($url, '?') !== false) {
+            list($url, $query) = explode('?', $url);
+        }
 
         if ($url !== '') {
             $url = self::resolveURL($url);
diff --git a/lib/classes/Widget.php b/lib/classes/Widget.php
index 90f3d56..f2dd3f0 100644
--- a/lib/classes/Widget.php
+++ b/lib/classes/Widget.php
@@ -231,7 +231,7 @@ class Widget
 
     public function __get($offset)
     {
-        return $this->template_variables[$offset];
+        return $this->template_variables[$offset] ?? null;
     }
 
     public function __set($offset, $value)
diff --git a/lib/classes/WidgetContainer.php b/lib/classes/WidgetContainer.php
index 5287305..1b0578e 100644
--- a/lib/classes/WidgetContainer.php
+++ b/lib/classes/WidgetContainer.php
@@ -24,12 +24,12 @@ abstract class WidgetContainer
     public static function Get()
     {
         $class = get_called_class();
-        if (static::$instances[$class] === null) {
+        if (!isset(static::$instances[$class])) {
             static::$instances[$class] = new static;
         }
         return static::$instances[$class];
     }
-    
+
     /**
      * Private constructor to ensure that the singleton Get() method is always
      * used.
@@ -39,12 +39,12 @@ abstract class WidgetContainer
     protected function __construct()
     {
     }
-    
+
     /**
      * Contains the widgets of the container
      */
     protected $widgets = [];
-    
+
     /**
      * Add a widget to the container.
      *
@@ -75,9 +75,9 @@ abstract class WidgetContainer
     public function insertWidget(Widget $widget, $before_index, $index = null)
     {
         $index = $index ?: $this->guessIndex($widget);
-        
+
         $inserted = false;
-        
+
         $widgets = [];
         foreach ($this->widgets as $idx => $wdgt) {
             if ($idx === $before_index) {
@@ -96,7 +96,7 @@ abstract class WidgetContainer
         }
 
         $this->widgets = $widgets;
-        
+
         return $widget;
     }
 
@@ -151,7 +151,7 @@ abstract class WidgetContainer
      *
      * @param String $index Index/name of the widget to remove.
      * @throws Exception if the specified position is invalid
-     */ 
+     */
     public function removeWidget($index)
     {
         if (!isset($this->widgets[$index])) {
diff --git a/lib/classes/calendar/CalendarScheduleModel.php b/lib/classes/calendar/CalendarScheduleModel.php
index 20f66c5..04c44b7 100644
--- a/lib/classes/calendar/CalendarScheduleModel.php
+++ b/lib/classes/calendar/CalendarScheduleModel.php
@@ -789,7 +789,7 @@ class CalendarScheduleModel
 
         $view = new CalendarWeekView($entries, 'schedule');
 
-        $view->setHeight(40 + (20 * $schedule_settings['zoom']));
+        $view->setHeight(40 + (20 * ($schedule_settings['zoom'] ?? 0)));
         $view->setRange($schedule_settings['glb_start_time'], $schedule_settings['glb_end_time']);
         $view->setInsertFunction("function (entry, column, hour, end_hour) {
             STUDIP.Schedule.newEntry(entry, column, hour, end_hour)
diff --git a/lib/classes/helpbar/Helpbar.php b/lib/classes/helpbar/Helpbar.php
index d2161fa..e01ad56 100644
--- a/lib/classes/helpbar/Helpbar.php
+++ b/lib/classes/helpbar/Helpbar.php
@@ -31,9 +31,9 @@ class Helpbar extends WidgetContainer
         $route        = get_route();
         $help_content = HelpContent::getContentByRoute();
         foreach ($help_content as $row) {
-            $this->addPlainText($row['label'] ?: '',
+            $this->addPlainText('',
                                 $this->interpolate($row['content'], $this->variables),
-                                $row['icon'] ? Icon::create($row['icon'], 'info_alt') : null,
+                                null,
                                 URLHelper::getURL('dispatch.php/help_content/edit/'.$row['content_id'], ['from' => $route]),
                                 URLHelper::getURL('dispatch.php/help_content/delete/'.$row['content_id'], ['from' => $route]));
         }
diff --git a/lib/classes/sidebar/LinkElement.php b/lib/classes/sidebar/LinkElement.php
index b38a145..8b20dbe 100644
--- a/lib/classes/sidebar/LinkElement.php
+++ b/lib/classes/sidebar/LinkElement.php
@@ -151,7 +151,7 @@ class LinkElement extends WidgetElement implements ArrayAccess
      */
     public function addClass($class)
     {
-        $this->attributes['class'] = $this->attributes['class']
+        $this->attributes['class'] = isset($this->attributes['class'])
             ? $this->attributes['class'] . " " . $class
             : $class;
         return $this;
diff --git a/lib/classes/sidebar/SidebarWidget.php b/lib/classes/sidebar/SidebarWidget.php
index 026ca0c..00735ac 100644
--- a/lib/classes/sidebar/SidebarWidget.php
+++ b/lib/classes/sidebar/SidebarWidget.php
@@ -91,7 +91,7 @@ class SidebarWidget extends Widget
      */
     public function render($variables = [])
     {
-        if ($this->id) {
+        if (!empty($this->id)) {
             $this->template_variables['id'] = $this->id;
         }
         return parent::render($variables);